Similarly, my monthly transfer, via WISE is done on 1st each month, and I specify the amount of Baht to be transferred, not the originating currency, thus avoiding any variations
That's very important for folk transferring close to the minimum 65k.
Just a guess, but I think most expats transfer much more, so never danger of dipping below 65k baht.
As for the OP, I suggest 12 month bank statement best option.
200 baht.